Heat exchange plate for plate heat exchanger, and plate heat exchanger

ABSTRACT

A heat exchange plate for use in a plate-type heat exchanger, and a plate-type heat exchanger having same. The heat exchange plate having a heat exchange portion and a port portion; fluids having different temperatures exchange heat with each other by means of the heat exchange portion; an opening used as the port of the heat exchanger is formed in the port portion. The heat exchange plate includes a first side and a second side in a direction perprendicular to the heat exchange plate; the port portion is provided with a contact porition that is in contact with the port portion of another heat exchange plate at the first side, and a protrusion protruding towards the second side relative to the contact portion. The heat exchange plate and the plate-type heat exchanger of the embodiments of the present invention can, for example, improve the quality of the port portion of the heat exchange plate of the heat exchanger.

CROSS-REFERENCE TO RELATED APPLICATION

[0000.1] This application is a National Stage application ofInternational Patent Application No. PCT/CN2020/124321, filed on Oct.28, 2020, which claims priority to Chinese Application No.201911063164.8, filed on Oct. 31, 2019, and Chinese Application No.201911189175.0, filed on Nov. 27, 2019, each of which is herebyincorporated by reference in its entirety.

TECHNICAL FIELD

Embodiments of the present invention relate to a heat exchange plate forplate heat exchanger, and a plate heat exchanger.

BACKGROUND

A plate heat exchanger comprises cover plates, heat exchange plates,connecting pipes, etc.

SUMMARY

An objective of embodiments of the present invention is to provide aheat exchange plate for a plate heat exchanger, and a plate heatexchanger having same, so that the quality of a port portion of the heatexchange plate of the heat exchanger can be improved, for example.

According to an embodiment of the present invention, a heat exchangeplate for a plate heat exchanger is provided, the heat exchange platecomprising: a heat exchange portion and a port portion, wherein fluidshaving different temperatures exchange heat with each other through theheat exchange portion, and an opening used as a port of the heatexchanger is formed in the port portion, wherein the heat exchange platecomprises a first side and a second side in a direction perpendicular tothe heat exchange plate; and the port portion is provided with a contactportion that is in contact with the port portion of another heatexchange plate on the first side, and a protrusion protruding toward thesecond side relative to the contact portion.

According to an embodiment of the present invention, the port portioncomprises a plurality of protrusions distributed in a circumferentialdirection around the opening.

According to an embodiment of the present invention, when viewed in thedirection perpendicular to the heat exchange plate, the plurality ofprotrusions are each in a circular, rectangular or trapezoidal shape.

According to an embodiment of the present invention, the port portioncomprises an annular contact portion and an annular protrusionsurrounding the opening, and the annular contact portion and the annularprotrusion adjoin each other.

According to an embodiment of the present invention, the port portioncomprises at least two annular protrusions surrounding the opening, andtwo of the at least two annular protrusions adjoin each other and havedifferent protrusion amounts relative to the contact portion; or two ofthe at least two annular protrusions are separated by the annularcontact portion.

According to an embodiment of the present invention, the port portioncomprises: a first annular portion surrounding the opening, wherein aninner edge of the first annular portion constitutes an edge of theopening; and a second annular portion surrounding the first annularportion and adjoining the first annular portion, wherein at least a partof one of the first annular portion and the second annular portionconstitutes the protrusion.

According to an embodiment of the present invention, a plurality ofcircumferentially-spaced parts of at least one of the first annularportion and the second annular portion constitute a plurality ofprotrusions; or one of the first annular portion and the second annularportion constitutes an annular protrusion; or one of the first annularportion and the second annular portion constitutes an annularprotrusion, and a plurality of circumferentially-spaced parts of theother of the first annular portion and the second annular portionconstitute a plurality of protrusions.

According to an embodiment of the present invention, the port portioncomprises: a first annular portion surrounding the opening, wherein aninner edge of the first annular portion constitutes an edge of theopening; a second annular portion surrounding the first annular portionand adjoining the first annular portion; and a third annular portionsurrounding the second annular portion and adjoining the second annularportion, wherein at least a part of at least one of the first annularportion, the second annular portion and the third annular portionconstitutes a protrusion.

According to an embodiment of the present invention, the second annularportion and the third annular portion protrude toward the second siderelative to a part of a surface of the port portion to constituteprotrusions, at least a part of the first annular portion constitutes acontact portion, and a protrusion amount of the second annular portionrelative to the contact portion is less than a protrusion amount of thethird annular portion.

According to an embodiment of the present invention, one of the firstannular portion, the second annular portion and the third annularportion constitutes an annular protrusion, and a plurality ofcircumferentially-spaced parts of a further one of the first annularportion, the second annular portion and the third annular portionconstitute a plurality of protrusions.

According to an embodiment of the present invention, the port portioncomprises: a plurality of annular portions surrounding the opening,wherein an inner edge of the innermost annular portion constitutes anedge of the opening, two adjacent annular portions of the plurality ofannular portions adjoin each other, and at least a part of at least oneof the plurality of annular portions constitutes the protrusion.

According to an embodiment of the present invention, at least one of theplurality of annular portions protrudes toward the second side relativeto a part of a surface of the port portion to constitute an annularprotrusion; or a plurality of circumferentially-spaced parts of at leastone of the plurality of annular portions protrude toward the second siderelative to the part of the surface of the port portion to constitute aplurality of protrusions.

According to an embodiment of the present invention, a plate heatexchanger is further provided, comprising: a plurality of heat exchangeplates, each being the heat exchange plate described above.

According to an embodiment of the present invention, protrusions of twoadjacent heat exchange plates hermetically connected to each other atthe port portions thereof protrude in directions away from each other,and a gap between two protrusions is in the range of 0.2-0.3 mm.

According to an embodiment of the present invention, protrusions of twoadjacent heat exchange plates hermetically connected to each other atthe port portions thereof protrude in directions away from each other, agap between two protrusions is in the range of 0.2-0.3 mm, and the gapbetween the two protrusions is filled with a brazing alloy for brazingthe plate heat exchanger, so as to braze the two protrusions together.

The heat exchange plate and the plate heat exchanger according to theembodiments of the present invention can improve the quality of the portportion of the heat exchange plate of the heat exchanger, for example.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view of a plate heat exchangeraccording to an embodiment of the present invention;

FIG. 2 is a schematic partial top view of the plate heat exchangeraccording to the embodiment of the present invention;

FIG. 3 is a schematic partial cross-sectional view of the plate heatexchanger according to the embodiment of the present invention alongline AA in FIG. 2 ;

FIG. 4 is a schematic partial cross-sectional view of a heat exchangeplate of a plate heat exchanger according to a first embodiment of thepresent invention along line AA in FIG. 2 ;

FIG. 5 is a schematic partial cross-sectional view of a heat exchangeplate of a plate heat exchanger according to a second embodiment of thepresent invention along line AA in FIG. 2 ;

FIG. 6 is a schematic partial cross-sectional view of a heat exchangeplate of a plate heat exchanger according to a third embodiment of thepresent invention along line AA in FIG. 2 ;

FIG. 7 is a schematic partial top view of a heat exchange plate of aplate heat exchanger according to a fourth embodiment of the presentinvention;

FIG. 8A is a schematic partial cross-sectional view of a heat exchangeplate of a plate heat exchanger according to a fifth embodiment of thepresent invention along a plane passing through an axis of a port shownin FIG. 2 ;

FIG. 8B is a schematic partial cross-sectional view of the heat exchangeplate of the plate heat exchanger according to the fifth embodiment ofthe present invention along another plane passing through the axis ofthe port shown in FIG. 2 ;

FIG. 9A is a schematic partial cross-sectional view of a heat exchangeplate of a plate heat exchanger according to a sixth embodiment of thepresent invention along a plane passing through the axis of the portshown in FIG. 2 ;

FIG. 9B is a schematic partial cross-sectional view of the heat exchangeplate of the plate heat exchanger according to the sixth embodiment ofthe present invention along another plane passing through the axis ofthe port shown in FIG. 2 ;

FIG. 10A is a schematic partial cross-sectional view of a heat exchangeplate of a plate heat exchanger according to a seventh embodiment of thepresent invention along a plane passing through the axis of the portshown in FIG. 2 ;

FIG. 10B is a schematic partial cross-sectional view of the heatexchange plate of the plate heat exchanger according to the seventhembodiment of the present invention along another plane passing throughthe axis of the port shown in FIG. 2 ;

FIG. 11A is a schematic partial cross-sectional view of a heat exchangeplate of a plate heat exchanger according to an eighth embodiment of thepresent invention along a plane passing through the axis of the portshown in FIG. 2 ;

FIG. 11B is a schematic partial cross-sectional view of the heatexchange plate of the plate heat exchanger according to the eighthembodiment of the present invention along another plane passing throughthe axis of the port shown in FIG. 2 ;

FIG. 12A is a schematic partial top view of a plate heat exchangeraccording to a ninth embodiment of the present invention; and

FIG. 12B is a schematic partial cross-sectional view of the heatexchange plate of the plate heat exchanger according to the ninthembodiment of the present invention along line BB shown in FIG. 12A.

DETAILED DESCRIPTION

The present invention will be further described below in conjunctionwith the accompanying drawings and specific implementations.

As shown in FIGS. 1 to 3 , a plate heat exchanger 100 according to anembodiment of the present invention comprises: a plurality of heatexchange plates 10; heat exchange spaces 20 formed between adjacent heatexchange plates 10 of the plurality of heat exchange plates 10; andports 30 formed in the heat exchange plates 10. Each of the ports 30 isconfigured to distribute a refrigerant to some heat exchange spaces 20of the heat exchange spaces 20.

Referring to FIG. 1 to 12B, the heat exchange plate 10 for the plateheat exchanger 100 according to embodiments of the present inventioncomprises: a heat exchange portion 11H and a port portion 11P; and anopening 12 formed in the port portion 11P and configured to form a port30 of the heat exchanger 100. The heat exchange portion 11H is providedwith a corrugated structure, so that fluids having differenttemperatures exchange heat with each other on two sides of the heatexchange portion 11H. The port portions 11P are substantially fittedtogether. The heat exchange plate 10 comprises a first side and a secondside (e.g., an upper side and a lower side of each of the heat exchangeplates 10 in FIGS. 3, 4, 5, 6, 8A, 8B, 9A, 9B, 10A, 10B, 11A, 11B, and12B) in a direction perpendicular to the heat exchange plate 10; and theport portion 11P is provided with a contact portion 16 that is incontact with the port portion 11P of another heat exchange plate 10 onthe first side, and a protrusion 15 protruding toward the second siderelative to the contact portion 16. For example, the port portion 11Phas a surface PS on the first side, and a part of the surface PS of theport portion 11P is in contact with the port portion 11P of another heatexchange plate 10.

In some embodiments of the present invention, referring to FIGS. 7, 8A,8B, 9A, 9B, 10A, 10B, 12A, and 12B, the port portion 11P comprises aplurality of protrusions 15 distributed in a circumferential directionaround the opening 12. For example, referring to FIGS. 7 and 12A, whenviewed in the direction perpendicular to the heat exchange plate 10, theplurality of protrusions 15 are each in a circular, rectangular ortrapezoidal shape.

In some embodiments of the present invention, referring to FIGS. 3, 4,5, 6, 8A, 8B, 10A, 10B, 11A, and 11B, the port portion 11P comprises anannular contact portion 16 and an annular protrusion 15 surrounding theopening 12, and the annular contact portion 16 and the annularprotrusion 15 adjoin each other. For example, referring to FIG. 5 , theport portion 11P comprises at least two annular protrusions 15surrounding the opening 12, and two annular protrusions 15 of the atleast two annular protrusions 15 adjoin each other and have differentprotrusion amounts relative to the contact portion 16; or two annularprotrusions 15 of the at least two annular protrusions 15 are separatedby the annular contact portion 16.

In some embodiments of the present invention, referring to FIG. 3 to12B, the port portion 11P comprises: a first annular portion P1surrounding the opening 12, wherein an inner edge P10 of the firstannular portion P1 constitutes an edge 120 of the opening 12; and asecond annular portion P2 surrounding the first annular portion P1 andadjoining the first annular portion P1, wherein at least a part of atleast one of the first annular portion P1 and the second annular portionP2 (e.g., one of the first annular portion P1 and the second annularportion P2) protrudes toward the second side to constitute a protrusion15. For example, one of the first annular portion P1 and the secondannular portion P2 protrudes toward the second side to constitute aprotrusion 15.

Each of the first annular portion P1 and the second annular portion P2has a predetermined width, and may be in a circular ring shape or othersuitable shapes according to the shape of the opening 12.

In some embodiments of the present invention, referring to FIGS. 7, 8A,8B, 9A, 9B, 10A, 10B, 12A, and 12B, a plurality ofcircumferentially-spaced parts of at least one of the first annularportion P1 and the second annular portion P2 (e.g., one of the firstannular portion P1 and the second annular portion P2) protrude towardthe second side to constitute a plurality of protrusions 15. A pluralityof stepped reinforcing structures are uniformly arranged in acircumferential direction of the annular portion around the opening 12of the heat exchange plate 10. For example, referring to FIG. 7 , noprotrusion 15 is provided in a region A and a protrusion 15 is providedin a region B. This structure can be modified according to the size ofthe opening and the size of the heat exchange portion.

In some embodiments of the present invention, referring to FIGS. 3, 4,5, 6, 8A, 8B, 10A, 10B, 11A, and 11B, the first annular portion P1protrudes toward the second side to constitute an annular protrusion 15;or the second annular portion P2 protrudes toward the second side toconstitute an annular protrusion 15.

In some embodiments of the present invention, referring to FIGS. 7, 8A,and 8B, one of the first annular portion P1 and the second annularportion P2 protrudes toward the second side to constitute an annularprotrusion 15, and a plurality of circumferentially-spaced parts of theother of the first annular portion P1 and the second annular portion P2protrude toward the second side to constitute a plurality of protrusions15.

In some embodiments of the present invention, referring to FIGS. 5, 10A,10B, 11A, 11B, 12A, and 12B, the port portion 11P comprises: a firstannular portion P1 surrounding the opening 12, wherein an inner edge P10of the first annular portion P1 constitutes an edge 120 of the opening12; a second annular portion P2 surrounding the first annular portion P1and adjoining the first annular portion P1; and a third annular portionP3 surrounding the second annular portion P2 and adjoining the secondannular portion P2, wherein at least a part of at least one of the firstannular portion P1, the second annular portion P2 and the third annularportion P3 protrudes toward the second side to constitute a protrusion15.

In some embodiments of the present invention, referring to FIG. 5 , thesecond annular portion P2 and the third annular portion P3 protrudetoward the second side to constitute protrusions 15, at least a part ofthe first annular portion P1 constitutes a contact portion 16, and aprotrusion amount of the second annular portion P2 relative to thecontact portion 16 is less than a protrusion amount of the third annularportion P3.

In some embodiments of the present invention, referring to FIGS. 10A,10B, 11A, and 11B, one of the first annular portion P1, the secondannular portion P2 and the third annular portion P3 protrudes toward thesecond side to constitute an annular protrusion 15, and a plurality ofcircumferentially-spaced parts of a further one of the first annularportion P1, the second annular portion P2 and the third annular portionP3 protrude toward the second side to constitute a plurality ofprotrusions 15.

In some embodiments of the present invention, referring to FIGS. 10A,10B, 11A, and 11B, one of the first annular portion P1 and the secondannular portion P2 protrudes toward the second side to constitute anannular protrusion 15, and a plurality of circumferentially-spaced partsof the third annular portion P3 protrude toward the second side toconstitute a plurality of protrusions 15.

In some embodiments of the present invention, referring to FIGS. 7, 8A,8B, 9A, 9B, 10A, 10B, 12A, and 12B, the plurality of protrusions 15 arearranged at equal intervals in the circumferential direction.

In some embodiments of the present invention, referring to FIGS. 7 and12A, when viewed in the direction perpendicular to the heat exchangeplate 10, the plurality of protrusions 15 are each in a circular,rectangular or trapezoidal shape.

In some embodiments of the present invention, referring to FIG. 3 to12B, the port portion 11P comprises: a plurality of annular portionssurrounding the opening 12, wherein an inner edge P10 of the innermostannular portion constitutes an edge 120 of the opening 12, two adjacentannular portions of the plurality of annular portions adjoin each other,and at least a part of at least one of the plurality of annular portionsprotrudes toward the second side to constitute the protrusion 15.

In some embodiments of the present invention, referring to FIG. 3 to12B, at least one of the plurality of annular portions protrudes towardthe second side to constitute an annular protrusion 15; or a pluralityof circumferentially-spaced parts of at least one of the plurality ofannular portions protrude toward the second side to constitute aplurality of protrusions 15.

In some embodiments of the present invention, referring to FIGS. 5, 10A,10B, 11A, 11B, 12A, and 12B, the port portion 11P comprises: at leastthree annular portions surrounding the opening 12, wherein an inner edgeP10 of the innermost annular portion constitutes an edge 120 of theopening 12, two adjacent annular portions of the at least three annularportions adjoin each other, and at least a part of each of at least twoof the at least three annular portions protrudes toward the second sideto constitute the protrusion 15.

In some embodiments of the present invention, referring to FIGS. 5, 10A,10B, 11A, 11B, 12A, and 12B, a protrusion amount of at least a part ofone of the at least two annular portions is different from a protrusionamount of at least a part of the other of the at least two annularportions; or a protrusion amount of at least a part of one of the atleast two annular portions is the same as a protrusion amount of atleast a part of the other of the at least two annular portions.

In some embodiments of the present invention, referring to FIGS. 5, 10A,10B, 11A, 11B, 12A, and 12B, each of at least two of the at least threeannular portions protrudes toward the second side to constitute anannular protrusion 15; a plurality of circumferentially-spaced parts ofeach of at least two of the at least three annular portions protrudetoward the second side to constitute a plurality of protrusions 15; or aplurality of circumferentially-spaced parts of one of at least two ofthe at least three annular portions protrude toward the second side toconstitute a plurality of protrusions 15, and the other of the at leasttwo of the at least three annular portions protrudes toward the secondside to constitute an annular protrusion 15.

In some embodiments of the present invention, referring to FIGS. 3, 4,5, 6, 8A, 8B, 9A, 9B, 10A, 10B, 11A, 11B, and 12B, protrusions 15 of twoadjacent heat exchange plates 10 hermetically connected to each other atthe port portions 11P thereof protrude in directions away from eachother, and a gap between two protrusions 15 is in the range of 0.2-0.3mm.

In some embodiments of the present invention, referring to FIGS. 3, 4,5, 6, 8A, 8B, 9A, 9B, 10A, 10B, 11A, 11B, and 12B, protrusions 15 of twoadjacent heat exchange plates 10 hermetically connected to each other atthe port portions 11P thereof protrude in directions away from eachother, a gap between two protrusions 15 is in the range of 0.2-0.3 mm,and the gap between the two protrusions 15 is filled with a brazingalloy for brazing the plate heat exchanger, so as to braze the twoprotrusions 15 together. In this way, the protrusions 15 can furtherreinforce the port portion 11P, for example.

In some embodiments of the present invention, the heat exchange plate 10is formed from a plate, such as by stamping. After the heat exchangeplate 10 is formed, the plate has an undeformed portion that is notdeformed toward the first side or the second side. The undeformedportion is in an initial plane, i.e., an undeformed plane in which theplate lies before being machined (e.g., stamped). Protrusions 15protrude from the initial plane toward the second side, and at least oneof a plurality of annular portions is not provided with a protrusion,i.e., is located in the initial plane.

According to embodiments of the present invention, referring to FIG. 3to 12B, the height, shape and size, etc. of each protrusion 15 can beadjusted according to the size of a corrugated structure in a heatexchange region, and the number of protrusions 15 around each openingcan also be adjusted accordingly. The height of each protrusion is lessthan that of each peak of the corrugated structure.

According to an embodiment of the present invention, when the size of aport of each heat exchange plate is larger and a larger number of heatexchange plates are stacked, a risk of warpage of the heat exchangeplates can be significantly reduced, a product pass rate can beimproved, and the flatness of the formed heat exchange plate in thevicinity of the opening for forming the port can be improved.

According to an embodiment of the present invention, a stepped structureis provided in the vicinity of the opening of the heat exchange plate,i.e., the original entire plane is reconfigured as two or more planeswith different heights, so that the structure can improve the flatnessof the heat exchange plate. In addition, this structure cansignificantly enhance the strength of the formed heat exchange plate inthe vicinity of the opening and prevent the occurrence of warpage.

According to an embodiment of the present invention, warpage deformationthat may occur if a large number of heat exchange plates are stacked oran opening of each heat exchange plate is larger is eliminated, theflatness of the heat exchange plate in the vicinity of the opening isimproved, the brazing quality of the heat exchange plates is improved,and the strength of the entire structure of the heat exchanger isfinally increased. In addition, the product pass rate is improved.

It should be noted that the features in one or more of the aboveembodiments can be combined into new embodiments. The features in anembodiment can be used in a further embodiment unless the features inthe embodiment conflict with the technical solution of the furtherembodiment.

While the present disclosure has been illustrated and described withrespect to a particular embodiment thereof, it should be appreciated bythose of ordinary skill in the art that various modi-fications to thisdisclosure may be made without departing from the spirit and scope ofthe present disclosure.

What is claimed is:
 1. A heat exchange plate for a plate heat exchanger,the heat exchange plate comprising: a heat exchange portion and a portportion, wherein fluids having different temperatures exchange heat witheach other through the heat exchange portion, and an opening used as aport of the heat exchanger is formed in the port portion, wherein theheat exchange plate comprises a first side and a second side in adirection perpendicular to the heat exchange plate; and the port portionis provided with a contact portion that is in contact with the portportion of another heat exchange plate on the first side, and aprotrusion protruding toward the second side relative to the contactportion.
 2. The heat exchange plate for a plate heat exchanger asclaimed in claim 1, wherein the port portion comprises a plurality ofprotrusions distributed in a circumferential direction around theopening.
 3. The heat exchange plate for a plate heat exchanger asclaimed in claim 2, wherein when viewed in the direction perpendicularto the heat exchange plate, the plurality of protrusions are each in acircular, rectangular or trapezoidal shape.
 4. The heat exchange platefor a plate heat exchanger as claimed in claim 1, wherein the portportion comprises an annular contact portion and an annular protrusionsurrounding the opening, and the annular contact portion and the annularprotrusion adjoin each other.
 5. The heat exchange plate for a plateheat exchanger as claimed in claim 4, wherein the port portion comprisesat least two annular protrusions surrounding the opening, and two of theat least two annular protrusions adjoin each other and have differentprotrusion amounts relative to the contact portion; or two of the atleast two annular protrusions are separated by the annular contactportion.
 6. The heat exchange plate for a plate heat exchanger asclaimed in claim 1, wherein the port portion comprises: a first annularportion surrounding the opening, wherein an inner edge of the firstannular portion constitutes an edge of the opening; and a second annularportion surrounding the first annular portion and adjoining the firstannular portion, wherein at least a part of one of the first annularportion and the second annular portion constitutes the protrusion. 7.The heat exchange plate for a plate heat exchanger as claimed in claim6, wherein a plurality of circumferentially-spaced parts of at least oneof the first annular portion and the second annular portion constitute aplurality of protrusions; or one of the first annular portion and thesecond annular portion constitutes an annular protrusion; or one of thefirst annular portion and the second annular portion constitutes anannular protrusion, and a plurality of circumferentially-spaced parts ofthe other of the first annular portion and the second annular portionconstitute a plurality of protrusions.
 8. The heat exchange plate for aplate heat exchanger as claimed in claim 1, wherein the port portioncomprises: a first annular portion surrounding the opening, wherein aninner edge of the first annular portion constitutes an edge of theopening; a second annular portion surrounding the first annular portionand adjoining the first annular portion; and a third annular portionsurrounding the second annular portion and adjoining the second annularportion, wherein at least a part of at least one of the first annularportion, the second annular portion and the third annular portionconstitutes a protrusion.
 9. The heat exchange plate for a plate heatexchanger as claimed in claim 8, wherein the second annular portion andthe third annular portion protrude toward the second side relative to apart of a surface of the port portion to constitute protrusions, atleast a part of the first annular portion constitutes a contact portion,and a protrusion amount of the second annular portion relative to thecontact portion is less than a protrusion amount of the third annularportion.
 10. The heat exchange plate for a plate heat exchanger asclaimed in claim 8, wherein one of the first annular portion, the secondannular portion and the third annular portion constitutes an annularprotrusion, and a plurality of circumferentially-spaced parts of afurther one of the first annular portion, the second annular portion andthe third annular portion constitute a plurality of protrusions.
 11. Theheat exchange plate for a plate heat exchanger as claimed in claim 1,wherein the port portion comprises: a plurality of annular portionssurrounding the opening, wherein an inner edge of the innermost annularportion constitutes an edge of the opening, two adjacent annularportions of the plurality of annular portions adjoin each other, and atleast a part of at least one of the plurality of annular portionsconstitutes the protrusion.
 12. The heat exchange plate for a plate heatexchanger as claimed in claim 11, wherein at least one of the pluralityof annular portions protrudes toward the second side relative to a partof a surface of the port portion to constitute an annular protrusion; ora plurality of circumferentially-spaced parts of at least one of theplurality of annular portions protrude toward the second side relativeto the part of the surface of the port portion to constitute a pluralityof protrusions.
 13. A plate heat exchanger, comprising: a plurality ofheat exchange plates, each being the heat exchange plate as claimed inclaim
 1. 14. The plate heat exchanger as claimed in claim 13, whereinprotrusions of two adjacent heat exchange plates hermetically connectedto each other at the port portions thereof protrude in directions awayfrom each other, and a gap between two protrusions is in the range of0.2-0.3 mm.
 15. The plate heat exchanger as claimed in claim 13, whereinprotrusions of two adjacent heat exchange plates hermetically connectedto each other at the port portions thereof protrude in directions awayfrom each other, a gap between two protrusions is in the range of0.2-0.3 mm, and the gap between the two protrusions is filled with abrazing alloy for brazing the plate heat exchanger, so as to braze thetwo protrusions together.